Intra-individual variability in cerebrovascular and respiratory chemosensitivity: Can we characterize a chemoreflex "reactivity profile"?
Respir Physiol Neurobiol
; 242: 30-39, 2017 08.
Article
em En
| MEDLINE
| ID: mdl-28279732
ABSTRACT
Intra-individual variability in the magnitude of human cerebrovascular and respiratory chemoreflex responses is largely unexplored. By comparing response magnitudes of cerebrovascular CO2 reactivity (CVR; middle and posterior cerebral arteries; MCA, PCA), central (CCR; CO2) and peripheral respiratory chemoreflexes (PCR; CO2 and O2), we tested the hypothesis that a within-individual reactivity magnitude profile could be characterized. The magnitudes of CVR and CCR were tested with hyperoxic rebreathing and PCR magnitudes were tested through transient respiratory tests (TT-CO2, hypercapnia; TT-N2, hypoxia). No significant intra-individual relationships were found between CCR vs. CVR (MCA and PCA), CCR vs. PCR (TT-N2 or TT-CO2) (r<0.2, P>0.3) response magnitudes. Statistically significant relationships were found between MCA vs. PCA reactivity (r=0.45, P<0.01) and PCR TT-N2 vs. PCR TT-CO2 (r=0.79, P<0.001) responses. Using qualitative and quantitative comparisons, we conclude that an intra-individual chemoreflex reactivity magnitude profile cannot be characterized. These data highlight the considerable between- and within-individual variability that exists in human cerebrovascular and respiratory chemoreflexes.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Qualitative_research
Limite:
Adult
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Female
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Humans
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Male
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article